redundant coma between last argument and `do`

[imba]

redundant coma between last argument and `do`

[somebee]

Imba has different precedence than Ruby when it comes to blocks. I've reasoned about it a few times, and have come to the conclusion that I like the Imba precedence better, but I cannot really remember why. Looks like we should go over it again, because right now it seems like a strange decision.

By the way, how it works in imba:

# It will only happen with callable arguments
save data do yes # block is called on data
save "data" do yes # block is called on save
save "data", 100 do yes # still called on save

# I personally never use comma, but use parens around the non-block args:
save(data) do yes

I need to go over this again and try to remember why this was supposedly a better idea :) I did discuss this briefly with @judofyr, maybe he can remember the reasoning?

in most cases i use parens too but for people who prefer parens-less syntax it's a useless payload to recall to put coma if last arg is callable.

[somebee]

The reason I'm leaning towards the existing syntax (besides compatibility) is the fact that it allows for this type of pattern, which I find myself using from time to time:

load something.map do |item|
    item.path

If we had ruby-like precendence, the block must be wrapped:

load something.map(do |item|
    item.path
)

I find it a bit clunkier to need to wrap the block itself, than to sometimes need to wrap the preceding arguments (or use a single comma). It seems easier to control where the do block is with the current syntax, but it's what I am used to, so hard to say.

[judofyr]

One "solution" would be to disallow ambiguous do blocks:

# ok:
load(something.map) do |item|
    item.path
# ok:
load(something.map do |item|
    item.path)
# ok:
load something.map(do |item|
    item.path)
# syntax error:
load something.map do |item|
    item.path

+1 on disallowing ambiguous do blocks